Hi guys, new member here. Had a betta all in one system. Did ok with it. Put two glofish tetras in it and they did well for 8 months then both spontaneously died the same night after a routine cleaning done the same way as always (that tank always used imagittarium fish water from petco. I just set up a new 20L sized aqueon tank with gravel, synthetic plants, a couple of statues, a marine land 200 filter, a bubbler, and a heater. It ran for a few days empty and the temperature was stable. The pH, nitrite, and nitrate tests were all normal (pH was 7.3) and this was with tap water treated with API testaments. I started five neon tetras, two black skirt tetras and two black skirt Molly in it last night. Both black skirt Molly were dead in the morning. What am I doing wrong???
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- Thread starter BigMak911
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You arent cycled. You cant cycle a tank in a couple of days.
Not being cycled doesnt normally kill fish overnight though. It could be they werent acclimated properly, could be they where sick when you got them.
20 litres isnt big enough for all those fish, along with you not being cycled thats a lot of bioload, a lot of waste, and it cant be processed out. Given this, the deaths could be caused by ammonia if that got high enough.
When you say your pH, nitrite, and nitrate are all normal, what do you mean? Could you give the numbers? What is your ammonia?
Do you know how to cycle a tank? Do you understand the nitrogen cycle?
Not being cycled doesnt normally kill fish overnight though. It could be they werent acclimated properly, could be they where sick when you got them.
20 litres isnt big enough for all those fish, along with you not being cycled thats a lot of bioload, a lot of waste, and it cant be processed out. Given this, the deaths could be caused by ammonia if that got high enough.
When you say your pH, nitrite, and nitrate are all normal, what do you mean? Could you give the numbers? What is your ammonia?
Do you know how to cycle a tank? Do you understand the nitrogen cycle?
I used api quick start which bills itself as allowing immediate stocking with fish. 20L isn't 20 liters in aqueon nomenclature. It's the long, as contrasted against high, 20 gallon tank. How do i cycle a tank with no living things in it? pH was 7.3. Temperature 78F and steady. Nitrite 0. Nitrate I can't remember the exact number, but it was low.
Those biological booster products like quick start might claim to cycle a tank but in reality the best you can hope for is to reduce the time to cycle a tank to weeks rather than months. They might not do anything, if the product isnt transported and stored in refrigerated conditions, the chances are anything beneficial will be killed off before you even get it home.
You can cycle tanks with no fish by dosing ammonia to artifically create waste and fuel the cycle. This is called a fishless cycle.
You have fish in there, so you need to undertake a fish in cycle. Test water daily, your target should be to keep ammonia + nitrite combined below 0.5ppm through water changes. Eventually you will consistently see ammonia + nitrite at 0ppm and your nitrate should be rising. This is when you are cycled for your current stock and you can add some more. This might mean daily water changes until your cycle starts to kick in depending on your parameters. It doesnt look like you have an ammonia test. You need that. Until you can test for ammonia a daily 25% water change should be enough to keep things in check until you confirm where you are.
Briefly, the nitrogen cycle is the process of bacteria breaking down waste in the form of ammonia, into nitrite, which is also harmful. Different bacteria then break down the nitrite into much less harmful nitrate. Your cycle normally cant process out nitrate, so you remove that with water changes. Cycling a tank is the process of growing the necessary bacteria, and as previous, it typically takes several weeks to grow enough to process out all the waste, even with products like quick start (assuming they actually work).
As nitrate is the end product of your cycle, the fact you are only seeing low levels is a clear sign of your tank not being cycled.
You can cycle tanks with no fish by dosing ammonia to artifically create waste and fuel the cycle. This is called a fishless cycle.
You have fish in there, so you need to undertake a fish in cycle. Test water daily, your target should be to keep ammonia + nitrite combined below 0.5ppm through water changes. Eventually you will consistently see ammonia + nitrite at 0ppm and your nitrate should be rising. This is when you are cycled for your current stock and you can add some more. This might mean daily water changes until your cycle starts to kick in depending on your parameters. It doesnt look like you have an ammonia test. You need that. Until you can test for ammonia a daily 25% water change should be enough to keep things in check until you confirm where you are.
Briefly, the nitrogen cycle is the process of bacteria breaking down waste in the form of ammonia, into nitrite, which is also harmful. Different bacteria then break down the nitrite into much less harmful nitrate. Your cycle normally cant process out nitrate, so you remove that with water changes. Cycling a tank is the process of growing the necessary bacteria, and as previous, it typically takes several weeks to grow enough to process out all the waste, even with products like quick start (assuming they actually work).
As nitrate is the end product of your cycle, the fact you are only seeing low levels is a clear sign of your tank not being cycled.
I agree with Aiken, I don't have any go-ahead for the type of products for an instant start of any aquarium, maybe I'm a bit dated but I prefer to wait for the full cycling of any tank that you install either fresh water or salt water, in personally, liquid bacteria have worked quite well for me when starting a tank, but it does not mean adding fish the next day or something like that, be patient my friend.
And just to be clear.
Im not saying that your cycle is the cause of your fishes death. Its unlikely that waste would build up to levels that will kill fish overnight because you arent cycled yet. I just see that you arent cycled and im trying to head off issues further down the line. We don't want you coming back in a couple weeks with the rest of your fish dead or dying because you arent cycling your tank properly.
The most common causes of overnight fish deaths are.
- Chlorine. But this would have killed all the fish.
- Sick or stressed fish. That just happens sometimes with new fish. Make sure you look at the health of the fish in the store before purchasing.
- Not acclimatising properly. Assuming that water parameters arent too different between your tank and the fish store water, float the bag to equalise temperatures and transfer the fish. Dont just tip them into your tank.
Im not saying that your cycle is the cause of your fishes death. Its unlikely that waste would build up to levels that will kill fish overnight because you arent cycled yet. I just see that you arent cycled and im trying to head off issues further down the line. We don't want you coming back in a couple weeks with the rest of your fish dead or dying because you arent cycling your tank properly.
The most common causes of overnight fish deaths are.
- Chlorine. But this would have killed all the fish.
- Sick or stressed fish. That just happens sometimes with new fish. Make sure you look at the health of the fish in the store before purchasing.
- Not acclimatising properly. Assuming that water parameters arent too different between your tank and the fish store water, float the bag to equalise temperatures and transfer the fish. Dont just tip them into your tank.
DrWho42
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